A new analysis of monitoring data from the Susquehanna River shows the stream is feeding an increasing amount of nutrients and sediment into the Chesapeake Bay, according to a U.S. Geological Survey press release.

The cause of the increase is sediment accumulation in upstream reservoirs, according to the report. The reservoirs are nearly filled, hampering their ability to trap sediment and nutrients before they wash downstream into the Bay. The USGS reports that, from 1996 to 2011, flow of phosphorus and suspended solids into the Chesapeake Bay increased 55 percent and 97 percent, respectively.

Tropical Storm Lee flooded the river in September 2011, exacerbating sediment flow.

The report documents thirty years of monitoring the Susquehanna River, which flows in to the bay from the northwest. The river sent record amounts of sediment and phosphorus into the bay in 2011.

Image: Conowingo Dam on the Susquehanna River (Credit: Wendy McPherson, U.S. Geological Survey)